title: A validated risk model to predict 90-day VTE events in postsurgical patients.
abstract: BACKGROUND
  VTE is the proximate cause of 100,000 deaths in the United States each year. Perioperative VTE risk among surgical patients varies by 20-fold, which highlights the importance of risk stratification to identify high-risk patients, in whom chemoprophylaxis can decrease VTE risk, and low-risk patients, for whom the risk-benefit relationship of prophylaxis may be unfavorable.
  
  
  METHODS
  We used data from a statewide surgical quality collaborative for surgical procedures performed between 2010 and 2012. Regression-based techniques identified predictors of 90-day VTE while adjusting for procedural complexity and comorbid conditions. A weighted risk index was created and was validated subsequently in a separate, independent dataset.
  
  
  RESULTS
  Data were available for 10,344 patients, who were allocated randomly to a derivation or validation cohort. The 90-day VTE rate was 1.4%; 66.2% of the derivation cohort and 65.5% of the validation cohort received chemoprophylaxis. Seven risk factors were incorporated into a weighted risk index: personal history of VTE, current cancer, sepsis/septic shock/systemic inflammatory response syndrome, age≥60 years, BMI≥40 kg/m2, male sex, and family history of VTE. Prediction for 90-day VTE was similar in the derivation and validation cohorts (areas under the receiver operator curve, 0.72 and 0.70, respectively). An 18-fold variation in 90-day VTE rate was identified.
  
  
  CONCLUSIONS
  A weighted risk index quantifies 90-day VTE risk among surgical patients and identifies an 18-fold variation in VTE risk among the overall surgical population.
authors.affiliation: Section of Plastic Surgery, Ann Arbor, MI.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Pannucci
authors.affiliation: Michigan Surgical Quality Collaborative, Ann Arbor, MI.
authors.forename: Sandra
authors.initials: S
authors.lastname: Laird
authors.affiliation: Division of Minimally Invasive Surgery, Ann Arbor, MI.
authors.forename: Justin B
authors.initials: JB
authors.lastname: Dimick
authors.affiliation: University of Michigan Hospitals, Ann Arbor, MI.
authors.forename: Darrell A
authors.initials: DA
authors.lastname: Campbell
authors.affiliation: Section of Vascular Surgery, Ann Arbor, MI. Electronic address: henke@med.umich.edu.
authors.forename: Peter K
authors.initials: PK
authors.lastname: Henke
mesh_terms: D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013514:Surgical Procedures, Operative / Q000009:adverse effects*; D014481:United States / Q000453:epidemiology; D054556:Venous Thromboembolism / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control
chemical_list: D005343:Fibrinolytic Agents